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M. M. MERRITT. GALVANOPLASUC PROCESS AND PRODUCT.

'APPLICATION FILED DEC. 8, 19| 7.

MATTI-IEW .EVIL MERRITT, 0F SOUTH MIDDLETON, MASSACHUSETTS, ASSIGNOR T0 COPPER PRODUCTS COMPANY, OF BOSTON, MASSACHUSETTS, A CORPORATION OF MAINE.-

GALVANOPLASTIC PROCESS AND PRODUCT.

Original application filed November 2, 1

To all whom it mal concern Be it known that I, Maru-inw M. lilnmcri'r, a citizen ofthe Lnited States, and a resident of South Middleton, county of Essex, Commonwealth of Massachusetts, have 1nvented an lmprovementin (iralvanoplastic Processes and Products,of whichv the fol' lowing descriptlon, 1n connectlon with the .In the drawings, which show one' form `0f an illustrative embodiment of my in vention:

'Figure l shows a manifold;

- Fig. '2 is a diagral'imia-tic section there- -through on the line 2-2 of Fig. 1.

Great difficulty has been experienced in constructing manifolds for aeroplane enf .gines ofthe requisite light welght which are strong enough'to withstand the constant and excessive vibrations occasioned byA the operation of the engine. Such manifolds are very likelyto develop cracks, particularly 'adjacent the bent 'portions thereof. It has heretofore. beenattempted to manufacture such manifolds by the electrolytic deposit of copper on cathodes of metal tfusible at a low temperature, and on cathodes of wax paint:

ed with graphite or other electrically con-` ductive material, the core being melted out after the electrolyte deposit. Manifolds made by the usual methods, above-described, have proved unsatisfactory becauseof. brittleness and coarseness of texture ofcthe .deposited metal, this brittleness being accentuated at points adjacent curved portions of the deposit.

I have found that the deposits made as be ore described are rendered more uniform in quality by intermittent 'immersion of the cathode, as by attaching the saine to a revolving wheel partially immersed in'thle Specification of Letters Patent.

Paten-ted Nov. 11, 1919.

917, Serial No. 199,811. Divided and thi-S application led December 8, 1917. Serial No. 206,295.

considerable portion thereof, preferably. at least one-half is only intermittently im.-

-mersed in the electrolyte. lvhile intermitpoints are, as heretofore made, likely to bev rough and brittle. I believe this to be due to the tendency of certain ingredients of the fusible metal, which is usually an alloy of lead, to be attacked by the electrolyte, and in some instances to be disassociated intonegative ions traveling from the cathode to the anode.

lVhere, on the-other hand, the cathode is formed of non-conductive material removable b v fusion, by a solvent, or otherwise, and the surface of which is coated with an electrically conductive paint, such as graphite, bronze powder and the like. the deposited copper, as heretofore practised, has been brittle and of slight tensile strength. As stated in my co-pending application. filed herewith. l believe this to be due to the comparatively coarse texture of the conductive coating which is necessarily full ofinterstices as compared with cast, rolled, or electrolytically deposited metal. The unevenness of attraction exerted by this surfacing ofthe cathode results in combining the deposited metal in relatively coarse crystalline formation. which renders it brittle and of slight tensile strength.

I have found that the deleterious effects of a cathode composed of metal having a low fusing-point may be minimized by coating the metal with a film of a foreign substance such as grease, and that if a layer of copper, preferably relatively thin, be elect-rolytically deposited subsequent to the application of lie` grease and the surface of this metal beic'oalted-with grease, that subsequent electrolytic deposits on the greased surface Will be of fine texture and of great tensile strength, the brittleness being grea/tly reduced, if not eliminated. If desired, the

structure may be laminated by the occasional 'futilizea non-metallic cathode lsuch as wax se that the entire cathode orafnr anyelectrically nonconductive=material removable by a solvent or otherwise, the

same being coated with a paint of electrolytically conductive materiel, I have found it of greet advantage to coat the surface of the electrically conductive material o1" paint with a thin-film of grease,I to deposit a relatively thin sheet of copper or otherl metal on the greased surface and, if desired, to provide e laniinatedstructure by subsequently occasionally interrupting `the electrolytic deposit and applying grease to the surface of the'deposited metal.

Throughout this application I have used the word grease generically to define any ,substance capable of forming a film 'of electrically non-conductive material over the surface on which metal is to be deposited.

After electro-deposition the core of the.

cathode may be removed hy fusion, by burning, by the use of a solvent orany. other suitable method.

I have utilized the Word fgalvanoplasticu in its broader sense to include any electrolytic processes in wh'ch the entire cathode or any portion thereof 1s 'removed subsequent to electro-deposition.

It is obvious that the cathodemay, if desired, be exterior to the surfacethereof on which metal is to be deposited, and that for'` some purposes my invention may be useful in connection with galvanoplastlc processes in which the'cathode can be Withdrawn Without change in the structure thereof.

While I have shown end describedone embodiment of my invention .and one method of practising the seme, it will: be

understood that major changes may he.

made, both in the product and the method of producing the seme,J Without departingl from the scope of my invention, which is best defined iii-the following'claims:fm

' l. The galvanoplastic process which comprises coating a mold or core with a coating of electrically conductive granular material,

coating said granular mafterial .With a foreign non-conductive substance, electrolytically depositing metahthereon, and subsequently removing'said vmold or core.

2; The galvanoplastic process Awhich comprises applying to the surface of e mold or core s, coating of electrically conductive l 

